Microelectro-mechanical systems (MEMS) relate to technologies based on an integration of mechanical elements, such as sensors and actuators, and/or electronics that are formed on a common substrate by microfabrication technology. MEMS components range in size from a few microns to a few millimeters. MEMS components are fabricated by microfabrication techniques that include techniques used to fabricate integrated circuits (IC) using IC process sequences (e.g., CMOS, Bipolar, or BICMOS processes). Integrated circuit microfabrication techniques have been used to create three dimensional arrays of electrical components.
Micromechanical components of MEMS systems are fabricated using “micromachining” processes that selectively etch away parts of the silicon wafer or add new structural layers to form the mechanical and electromechanical devices. By combining silicon based microelectronics and micromachining, MEMS technology creates systems and devices in a single chip. MEMS augments the computational ability of microelectronics with the sensing and control functions of microsensors and/or microactuators.
In recent years, advances have been made in the field of neurobiology. An important aspect of further advancement is observation of spatiotemporally distributed neural activity. MEMS technology has been applied to develop a self-anchoring MEMS intrafascicular neural electrode as disclosed by International Publication No. WO 2009/012502 A1, which is expressly incorporated herein by reference.
Several studies using animals have successfully investigated the use of movable microelectrodes that can be precisely positioned in the brain or can be moved in the event of neural-electrode interface failure. However, the size and weight of the movable microelectrodes are often large and interfere with or impair animal movement and/or behavior. Therefore, there is a need for a movable microelectrode device that can be integrated with advanced signal conditioning and control circuitry towards a fully autonomous microimplant in the brain. There remains a need for apparatus for sensing spatially distributed neural activity and for recording that activity.